Ainslie on board but Oracle lose

Ainslie on board but Oracle lose

Ainslie on board but Oracle lose

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Sir Ben Ainslie could not inspire Oracle to victory in either of Thursday's races

Great Britain's four-time Olympic champion Sir Ben Ainslie was unable to immediately revive Oracle Team USA's faltering America's Cup bid after he was drafted into action in San Francisco on Thursday.

Oracle confirmed before Thursday's double header that Ainslie, the most successful Olympic sailor ever, would replace tactician John Kostecki as they aimed to halt Emirates Team New Zealand's charge towards victory.

Ainslie's presence, however, failed to make an impact as the Kiwis won both of Thursday's races to move to within three wins of claiming the Auld Mug.

The challengers effectively lead six race wins to minus one after Oracle were docked two points before the regatta for illegally modifying their 45-foot catamaran in the event's warm-up series.

The scandal was regarded as one of the biggest cheating controversies in the 162-year history of the race.

Oracle have made a habit of being out-manoeuvred in the deciding series - one of the factors behind Ainslie's promotion - but there was little they could do as Team New Zealand's superior upwind speed again saw them hustle by in race six to win by 46.5 seconds.

It was more of the same in race seven, the victory margin this time by more than a minute, to render Ainslie's inclusion a mere side note to their seemingly unstoppable surge towards victory.

Ainslie had been expected to take over from Kostecki after he worked with the team during Wednesday's rest day.

A Kostecki tactical mistake was blamed for defeat in race five on Tuesday, after which Oracle exercised their right to postpone race six and give Ainslie 24 hours to prepare himself.

"We've decided to make a change in the back and bring Ben Ainslie onboard," skipper Jimmy Spithill said in a statement on the team's official website before Thursday's races.

"While making crew changes has always been an option, we understand there's a risk that comes with it. JK is a great team-mate and a tremendous asset to our program, and he is supportive of the decision."

Ainslie, who was knighted in March, added: "It's a tough decision to make, but I'm happy to step up and do what's best for the team.

"I have a huge amount of respect for JK and really appreciate his support in making the transition."